Gage for grinding twist or flat drills



(No Model.) 2 Sheets-Sheet 1.

A. F.- BREWER. GAGE FOR GRINDING TWIST 0R FLAT DRILLS.

No. 403,175. Patented May 14, 1889..

2 b Bu 8 h S W e e h S 2 R E W E R B R A m d 0 M o W GAGE FOR GRINDING TWIST 0R FLAT DRILLS.

.No. 403,175. Patented May 14-, 1 889.

frzvewr: 5 ffirewzr N. PETERS. Pholu-Limn n lmr, Washington, D. C.

UNITED STATES PATENT OFFICE.

ADOLPH FIBREIVER, OF SAN FRANCISCO, CALIFORNIA.

GAGE FOR GRINDING TWI'ST OR FLAT DRILLS.

SPECIFICATION forming part of Letters Patent N 0. 403,175, dated May 14, 1889.

Application filed August 15 1888. Serial No. 282,820. (No model.)

To aZZ whom it may concern.-

Be it known that I, ADOLPH F. BREWER, a citizen of the United States, residing in the city and county of San Francisco, and State of California, have invented a new and useful Improvement in Adjustable Standard Bevel- Gages for Grinding Twist-Drills, of which the following is a specification.

This invention relates to gages for grind ing-drills, and the novelty will be fully understood from the following description and claims, when taken in connection with the annexed drawings, in which- Figure 1 is a front view of my improved device. Fig. 2 is a side elevation of the same, showing it applied to a twist-drill. Fig. 3 is a plan View with the drill in position. Fig. 4c is a vertical central sectional view with the drill removed, and Fig. 5 is a perspective view of the slide for adjusting the gage rule or arm.

Referring by letter to the said drawings, A indicates the box-square, which may be of the form usually employed, being adapted to receive within its walls a drill to be operated upon. This box-square, which is of an angular form, isprovided at its upper end and at the angle of the wings or walls with a transversely-arranged box, H, which is designed to serve as a guide for a slide, as will be presently explained. The box H is provided with a transverse slot, a, and the walls at each side of this slot are provided with shoulders or flanges b. j

E indicates an adjusting-screw, which is arranged in the box H, and has a bearing in one end thereof, as shown.

d indicates an adjusting-slide for the gage rule or arm. This slide d is of a form substantially as shown in Fig. 5 of the drawings,-

having a square portion, 6, provided with an internally-threaded aperture to receive the threaded rod or screw E. It is furthermore provided with a reduced rectangular portion, f, which travels in the slot at of the box H, and receives a correspondingly-shaped aperture in the gage rule or arm 13, and a threaded extension, g, to receive a wing-nut, h, whereby the slide and arm may be secured in position with respect to the box-square. It will thus be seen that by manipulating the screw E the slide and gage rule or arm B may be moved to the desired point, and by means of the wing-nut h the whole fixed to the boxsquare.

When the wing=nut has been loosened on the threaded extension of the slide, the latter, together with the gage-rule, may be moved to the desired point across the box H.

The upper end of the box-square or the guide-box H is beveled, as shown at I. This bevel may be on any desired angle, but preferably on an angle of about fifty-nine degrees, and the gage rule or arm B is designed to have a bearing on this beveled surface.

The gage-rule B has its inner end formed as shown, so as to bear upon the guide-box, and is provided with an aperture to receive the reduced square portion of the slide d. From this apertured portion of the gage-rule extends an oblique branch which is slotted. Arranged in the slotted portion of the branch is a threaded rod, 1, which is provided at its outer end with a head, J, whereby it may be manipulated.

F indicates a guide-mortise or pointer,which is provided with an internally-threaded aperture to receive said screw or rod i, and is adapted to travel in the slot of the arm when the rod has been turned.

In operation I place the box-square upon a drill, as shown in Fig. 2. If the drill is small, the cutting-edges are in lines close to the cen ter; but in large drills they are off the center. The drill is then ground to the desired point.

Having described my inventiomwhat I claim is* 1. The combination, with the box-square and gage-rule, of a guide-box formed thereon and provided with a bevel, as described, and adapted to serve in sustaining the gage-rule, substantially as specified.

2. The combination, with a box-square provided with a guide-box beveled as described, of a slide arranged in said guide-box, a gagerule connected with said slide, and a set-screw for adjusting the slide and rule, substantially as specified.

3. The combination, with a box-square, of a gage-rule connected therewith, and a screw for laterally adjusting the rule with relation to the square, substantially as specified.

4. The combination, with the gage-square provided with the guide-box beveled as deslide, and a Wing-nut to receive the reduced scribed, of the slide arranged in said box and threaded portion of said slide, substantially to having an internally-threaded aperture, a reas specified.

duced rectangular portion and a reduced ADOI F BRFVER 5 threaded p0rti011,a set-screw journaled inthe guide-box and engaging the threads in the \Vitnesses:

slide, the gage-rule having an aperture to re- EUGENE II. THORP,

eeive the reduced rectangular portion of the ORVILLE C. BALDWIN. 

